Particle size distribution analyser

ABSTRACT

A device for analysing the particle size distribution of very small particles such as sand, etc., from a given quantity of water of river or sea by precipitation onto a receiving plate rotating at a very low speed in a body of water, larger particles descending earlier than smaller ones, whereby the particles of different sizes are separately precipitated onto the receiving plate and collected according to size distribution.

D United States Patent 1191 1111 3,844,413 Mizushima Oct. 29, 1974 I541PARTICLE SIZE DISTRIBUTION 2,887,227 5/1959 Dunham 209/209 ANALYSER3,222,925 12/1965 Kracke et a]. 73/28 x 3,405,548 10/1968 Samarzopoulos73/432 PS X [75] Inventor: Taken Mizushima, Tokyo, Japan I FOREIGNPATENTS OR APPLICATIONS [73] Asslgnee' g f wfgg ggf Kabush'k' 2,053,4484/1971 France 209/209 [22] Filed: June 4, 1973 Primary Examiner-Frank W.Lutter Assistant ExaminerRalph J. Hill [2]] Appl' 366688 Attorney,Agent, or Firm-Cushman, Darby &

Cushman [30] Foreign Application Priority Data July 26, 1972 Japan47-74765 [57] ABSTRACT A device for analysing the particle sizedistribution of (gill. 209/20gb'37g/g/ld3 very Small particles Such assand, etc" from a given [58] Fieid 210/83 quantity of water of river orsea by precipitation onto E 73/6l 432 a receiving plate rotating at avery .low speed in a body of water, larger particles descending earlierthan [56] R f n Cit d smaller ones, whereby the particles of differentsizes e e are separately precipitated onto the receiving plate UNITEDSTATES PATENTS and collected according to size distribution. 1,046,44712/1912 Delameter 209/209 2,702,122 2/1955 Joaquin 209/209 3 (351M513Drawmg PARTICLE SIZE DISTRIBUTION ANALYSER BACKGROUND OF THEINVENTION 1. Field of the Invention This invention relates to a devicefor sorting and classifying very small particles.

2. Description of the Prior Arts When the water of river or sea istreated for use as industrial water and drink water, it is required tochemically analyze the quality of water as well as to remove mineralssuch as sand particles. In this connection, it is necessary to know whatsizes of particles of sand are contained in a determined amount of waterof the river or sea. Conventionally, there is used a standard sortingdevice having a sieve of 0044mm mesh, which is the minimum size of thesieve available in accordance with 118 (Japanese Industrial Standards).

A known automatic particle size measuring device includes a water vesselin which a balance is provided to measure particles stirred up anddescended onto a receiving dish, thereby measuring the distribution ofthe particle size, based upon the amount of particles precipitated in adetermined time.

Such a device requires a relatively large amount of samples to operatesatisfactorily.

However. it is generally difficult to obtain such a large amount ofsamples of the water of river or sea.

Furthermore, such a device can analyze distribution of particles sizesbut since the particles precipitated on the balancedish are not sortedaccording to the sizes thereof, it is not known what sized particles arecontained in the samples in what percentage.

SUMMARY or THEINVENTIGN It is the object of this invention is to providea device having an easy-operable and simplestructure to accuratelyanalyze, sort and measure particles even with a small amount of samples.

The device comprises a transparent water vessel, a top sealing cover, ashaft perpendicularly passing through said cover and rotatably carriedby said cover, an horological mechanism to drive said shaft, a firstinserted cap member having two concentric side walls and fixed to saidshaft to be co-rotatable therewith, a second cup member having twoconcentric side walls adapted to receive said two concentric side wallsof saidfirst cup member, said second cup member being carried by saidshaft to be adjustable of its position along said shaft. and an annulardish mounted in said in said second cup member in an annular spacedefined the two concentric side walls thereof, said first cup memberhaving a sample inlet port opening to said, annular space.

BRIEF DESCRIPTION or THE DRAWINGS FIG. I is a longitudinal section of anembodiment of the device according to this invention; and

FIGS. 2 and 3 are plan views of two examples of the annular dishes to beincorporated in the device as shown in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following, thisinvention will be described of a preferred embodiment with reference tothe accompanied drawings.

A water vessel I made of a transparent synthetic resin or glass havingfeet 2 is equipped with a top cover 3 sealing the upper opening of saidvessel, and a rotary shaft 4 is perpendicularly passing through thecover 3 at the center of the vessel 1.

The rotary shaft 4 is abutting against the bottom of the vessel I at thelower-most end thereof where it is conically shaped and is carried atits upper portion by rollers 6 of a bearing 5 provided at the cover 3.The shaft 4 is in turn carrying a gear 7 at its upper end portion, whichis in meshing engagement with a gear 8 of an horological mechanism 9 tobe driven by the mechanism.

An upper end plate 11a of a first cup member 10 is fixed to the rotaryshaft 4 and inner and outer cylindrical side walls 11b, 11c integrallyconnected with the end plate 11a extend downward therefrom.

The end plate 11a is provided with a funnel shaped sample inlet port 12.

A second cup member 13 includes a bottom plate 14a through which therotary shaft 4 passes in a manner to permit axial movement therebetween.Side walls 14b, of the second cup member 13 receive therebetween theside walls l lb, llc of the first cup member 10, thereby defining anannular space closed at upper and lower ends thereof. The bottom plate14a is provided with several draining holes 15 opening in the region ofthe annular space. An annular receiving dish 16 is placed at the bottomof the annular space to fit the side walls 14b, 14c.

The receiving dish 16 may, for example, be of the shapes in FIGS. 2 and3. The receiving dish 16 shown in FIG. 2 is used to analyse and sort.particles of diameter d in the range of 0.005 d 0.05mm. The annular dishis divided by partitions 17 to provide separate receiver sections A, B.C, and D on the receiving dish 16. The receiving dish 16 shown in FIG. 3provides receiver sections E and F adapted to sort particles two partsof d 0.005mm and d 0.005.

The bottom plate 14a of the second cup member 13 is provided with astopper 18 to adljustably mount the second cup member 13 to the shaft 4with respect to its height.

The shaft 4 is provided with centimetric measuring marks 19 at the lowerend portion thereof for the convenience of adjusting the height of thesecond cup member. Said centimetric measuring marks 19 is converselymarked from up to down to give the height h from the inlet point of thesample introduced through the inlet port 12 to the bottom of thereceiving dish 16.

The particles to be sorted in the receiver sections A, B, C, and D ofthe receiving dish 16 are within the range of 0.005 d 0.05mm particlesize as mentioned above. The descending speed (cm/sec) of the particlesvaries according to water temperature and specific gravity of theparticles and as a result of experiments, the inventor has obtained thedata as shown in Table I. Table I. Descending speed (cm/sec) of theParticles in ewmn Thus, assuming conditions that the descending height his 20cm and the water temperature is 15C, a particle having diameter of0.05 mm and specific weight 2.65

shows descending speed of 0.196 cm/sec and takes about 1 min. 40 sec toreach the receiving dish. For the same conditions, another particle of0.005 mm diameter and 2.65 specific weight shows descending speed of1.96 X 10' cm/sec and takes about 2 hours and 46 min. to reach thereceiving dish.

The sorting device according to this invention is of descending andprecipitating type wherein the samples are dropped in the still waterthereby analyzing the particles regardless the quantity of the samples,and since the samples descend perpendicularly in the water, the weightof the samples themselves is clearly distinguished whereby nodifferently-sized particles are mixed in a group of the particlesprecipitated on a funnel shaped section. The device itself is operatedwith a simple mechanism and construction in such a manner that thereceiving dish 16 is rotated with an horological gear through gears 9,10, thereby allowing cheaper installation cost, wherein the height (h)of the receiving dish 16 is indicated on the given centimetric marksthrough the transparent vessel 1. By the transparent vessel, there areobtained other features of permitting to check the descending andprecipitating condition of the samples. Furthermore the device is usedto analyze and sort the particle sizes of medicines and other materialswhich are not soluble.

As discussed hereinbefore, the sorting device of this invention can bewidely used in the industries for sorting and classifying particles.

Modification to the above embodiment will be made without departing fromthe spirit and technical scope of this invention.

What lclaim is:

1. A device for sorting and classifying very small particles comprising:

a. a transparent water vessel,

b. a top sealing cover,

c. a shaft perpendicularly passing through said cover and rotatablycarried by said cover,

d. an horological mechanism to rotatably drive said shaft,

e. a first inverted cup member having two concentric side walls andfixed to said shaft to be co-rotatable therewith,

f. second cup member having two concentric side walls adapted to receivesaid two concentric side walls of said first cup member, said second cupmember being carried by said shaft and including means for adjusting itsposition along said shaft, and

g. an annular dish mounted in said second cup member in an annularspaced defined by the two concentric side walls thereof, said first cupmember having a sample inlet port opening to said annular space. 2. Adevice according to claim 1, wherein said annular dish is separated intosectoral portions by partitions.

sition of said second cup member on said shaft.

1. A device for sorting and classifying very small particles comprising:a. a transparent water vessel, b. a top sealing cover, c. a shaftperpendicularly passing through said cover and rotatably carried by saidcover, d. an horological mechanism to rotatably drive said shaft, e. afirst inverted cup member having two concentric side walls and fixed tosaid shaft to be co-rotatable therewith, f. second cup member having twoconcentric side walls adapted to receive said two concentric side wAllsof said first cup member, said second cup member being carried by saidshaft and including means for adjusting its position along said shaft,and g. an annular dish mounted in said second cup member in an annularspaced defined by the two concentric side walls thereof, said first cupmember having a sample inlet port opening to said annular space.
 2. Adevice according to claim 1, wherein said annular dish is separated intosectoral portions by partitions.
 3. A device according to claim 1,wherein said rotatable shaft is provided with means for measuring theposition of said second cup member on said shaft.